Answer:
v = 1.2 m/s
Explanation:
The wavelength of the waves is given as the horizontal distance between the crests:
λ = wavelength = 5.5 m
Now, the time period is given as the time taken by boat to move from the highest point again to the highest point. So it will be equal to twice the time taken by the boat to travel from highest to the lowest point:
T = Time Period = 2(2.3 s) = 4.6 s
Now, the speed of the wave is given as:

where,
v= speed of wave = ?
f = frequency of wave = 
Therefore,

<u>v = 1.2 m/s</u>
Answer:
4.6×10^-7 m or 0.46nm
Explanation:
From
Wo= hc/λ
Where:
Wo= work function of the metal
h= planks constant
c= speed of light
λ= wavelength
λ= hc/Wo
λ= 6.6×10^-34 × 3×10^8/4.30×10^-19
λ= 4.6×10^-7 m
Answer:
265 J
Explanation:
where KE is kinetic energy, PE is potential energy, m is the mass of an object, v is the speed, h is the height and g is acceleration due to gravity.
Substituting 19.7 Kg for mass, 0.934 for h, 2.93 for v and 9.81 for g then

Mass of bottle + cooking oil = 1.3 kg
Mass of bottle + 1/2 cooking oil = 0.9 kg
Thus half cooking oil = 1.3 - 0.9
= 0.4 kg
Mass of cooking oil in a full bottle = 0.4 × 2
= 0.8 kg
Therefore the mass of the empty bottle
= 1.3 - 0.8
= 0.5 kg